Shock absorber for vehicles



Jan.l22, 1929. 1,699,742

R. P. LANSING SHOCK ABSORBER FOR VEHICLES Filed Jan. 6, 1925 Patented Jan. 22, l929.

entren stares RAYMCND P. LANSING, OF MONTCLAIR, NEW JERSEY.

SHOCK ABSRBER FOR VEHICLES.

Application inea January e, 1925. serial No. 752.

I lily invention relates to shock absorbers, or appliances for controlling the action of vehicle springs. Y

'lfhe general object of the invention is to 5 provide an appliance of the friction type Which is strong, durable and of simple construction, and therefore may be produced at a moderate cost.

A more particular object is to provide an appliance which includes relatively revoluble structures, a relatively large number of friction elements or surfaces 'operative between these structures in order to give a very substantial friction effect with a relatively moderate pressure applied to the surfaces, yieldable means or a spring, and inclined elements or screw threads eo-operating With the yieldable means to produce or control the friction pressure, Whicn preferably differs in the different directions of relative movement of the revoluble structures. y i y A further object is to so arrange or adapt the structure that a relatively large .number of friction members or discs may be employed, and they and the structure in general may be of mode ate diameter While providing the desired friction resistance with moderate pressure values.

A. more particular object is to improve the action of shock absorbers of this type by avoiding.)` or limiting excessive movement of certain of themovable elements in one direction, as sufficiently explained.

Another object is to provide an improved retaining structure or `thrust bearing for securing relatively revoluble parts Without considerable or noticeable lost motion.

Another object is to improve the mechanial structure or details of devices of this class in various Ways, as explained beloiv.

'lhe present invention as represented by the specific embodiment here shmvn. is similar in certain general and .specific features to other of my inventions disclosed in pending applications, and especially to the structure shown in my copending application Ser. No. 743,924, filed Oct. 16, 1924,` "With important modifications and improvements.

rlhe characteristics and advantages of the invention are further sufliciently explained in connection with the following detail description of the accoimoanying drawing, lwhich shows one exemplifying embodiment of the invention. After considering this embodiment, persons skilled in themart will understand that many variations `may be made Within the principles of the invent-ion, and IV contemplate the employment of any. structures that are properly Within the scope of the appended claims.

Fig. l is a rear elevation of a shock absorber embodying the invention in one form; that is a view looking at the side of the base plate 1 Which is secured against the outer face of a vehicle side frame member. l

Fig'. 2 is a longitudinal, horizontal section of the same, in they plane 2--2, Fig. l. Fig. 3 is a transverse section. Fig. 4 is a front elevation. A main or base plate l is provided with ears 2 for attachment to a part of a motor vehicle such as'a chassis frame member,by screws or bolts 3 or like` means, or in some cases the base may have an articulated connection to the frame, as Well understood `in this art. The. base has a short extension or sleeve 4 terminatingin teeth or `jaivs 5. A shaft or spindle "5 has an enlargement 7 closely fitting in sleeve 4. The` engaging faces of the enlargement 7 andthe sleeve may be serrated to prevent relative rotation, although there is no considerable force tending to cause spindle rotation. At the inner end the spindle has a head 8 fitting in` a counterbore in the base plate. i

A revoluble structure, designated asa Whole by reference numeral 9, is arranged for rotation or oscillation about the spindle. This structure includes an inner` member 10 which may be described for identification and Without necessary limiting significance as an inner housing or cover member, which is usually of pressed sheet metal and includes the cylindrical portion to which the numeral 10 is directly applied, an outer flange l1, and an inner flange A12. The central or hub portion 13 of a lever or arm 14 is secured to flange 11 by a convenientmeans, such as rivets `15, or screws if it is desired to readily separate the parts. Usu` ally a gasket -lis placed between the hub and flange. An outer cover 17 is secured to the outer face of hub `18, usually by means of the rivets 15, and With an interposed gasket 18. l

A flat ring 2() is located on the outer face of plate l and centered at the axis of spindle 6, and a portion 210i flange 120i' the inner rotor member constitutes a bearing plate or surface bearing upon a portion of the outer face olE ringr` 20. This ring is free to turn in relation to the outer tace of base plate l, and has an appreciable friction value, but usually serves mainly as a thrust bearing with moderate or negligible friction etl'ect and for that purpose is preferably made of some such materiales bronze, which i provides a good bearing with a low iriction coefficient7 when in contact with steel, and the friction eifect is further reducedby the small average radius of the ring. A packingr consist-ing;r ot a ring Q2 oit telt or other suitable compressible material is usually placed about ring 20, and is located or centered about the spindle by a channel 23 in the base plate. This packing aids in retaining grease or otherlubricant and-also excludes dirt and moisture from the bearingr surfaces of ring 20.

A cylindrical thimble 25 engages thc outer face of sleeve 4 with a tight or press fit7 and its :inner end portion serves to properly center ring' 20, which, however, is preferably permitted to rotate in relation to base plate 1 by slight clearance around the thimble, in order to permit Wear to occur both on the inner and out-er ring faces, and so to increase .its life. A short cylindrical spacing sleeve 2G located with a bearing fit about the cylindrical portion ot thimble 26 and is restrained from outwardmovement by a flange 27 on the thimble. The inner end of the spacer rests on a port-ion of the outer surface of ring with a bearing tit or clearance. At its inward end the outer surface of spacer 2G is of slightly reduced diameter to engage within the circular aperture inplate 1 2 with a tight or press fit, to substantially lock these parts together and prevent relative rotation or axial nmvement.

The parts just described constitute a retaining and bearing structure or arrangement for the entire rotor-structure S), Lever 'll secured to the inner rotor njielnber 10, outer cover 1T and other parts later referred to. oscillate as a unit about the fixed tliimble the inner surface of spacer 26 acting as a radial bearing` for this movement. Any thrustv effect or material axial play is also 'lalteii up by the spacer 2G and plate 1Q co operatingr with tinter 20, and by the sparerw cti-operating With flange QT of thimble 25. There is therefore no objectionable or perceptible play of the rotor structure; In assembling the parts the spacer Q6 usually first pres *ed into position-Witliin the` aperture of plate 12, and after the plate with certain other parts is put in position about the spindle and before other parts later referred to are positioned, thimble pressed into position and thereafter' the described parts of the rotor structure With other parte which are later positioned,is retained for rotation and against end movement in the described manner.

The lever arm 14 muy desirably be of' pressed sheet metal and in such cases is desirably `formed with an outer flange 30 extending about the entire outline ot the lever, inchulinpr its hub 13, to provide suliicient strength and rigidity. Desir-ably also, the central portion of the hub is drawn or pressed to provide an inwardly projecting' cylindrical flange 31, which is channeled r completely slotted to provide spaced jaws 3Q with intermediate channels or slots 33 coni stituting s plineways to receive spaced teeth or splines 3 4 formed on the outer peripheries of a suitable plurality of Jfriction plates or discs 35, conveniently identified as rotor discs, since they are secured in the described manner to move With the rotor structure While permitted suitable axial movement. The spline or jaw structure 3l is evidently not necessarily integral with the lever 14.

At the outward end ot the lever is a ball or other suitable Fitting 36 for the connection ot thelever to a part of a vehicle such as the axle, by a suitable link, or in any known or suitable manner. i A device conveniently identified as a shifter 40 is located on spindle (S With a bearing fit to provide for axial movement. At its inner end the shifter has spaced jaws 4:1 cooperatingr with sleeve jaws 5 to prevent shifter rotation While permitting axial movement. The longitudinal dimensions ot the jaws 5 and 41 are such that. when the shifter is properly positioned by co-operation with other parts as later explained, there is very substantial clearance longitudinally between the outer ends of the sleeve jaws 5 and the contronting;r ends of the shifter, and between the inner ends of the shifter jaws 4l and the confronting end oi the sleeve. These clearances are provided to prevent any contact or seating ol the shifter against the sleeve in its inward movenient. The inward portion of the shifter including` its jaws` has a substaiitial clearance Afrom tliimble Q5. j

A suitable pluraiitf,7 of screw threads lo are 'formed on the outer end of the shifter. and these co-ojierate with threads alti :formed in the bore ot'a nut or plate fil, which may otherwise in some cases be conveniently designated a pressure menihen since one ot its important 'functions lo convev j troni the sliit'ter t-o theA friction di. plate or pressure member is provided with means for properly connecting to it friction discs which are interspaced with: the rotor discs For manufacturing conreni ence and economy such means prefs-nabij consists of a separate pressed or drawn metal fitting 5l, which has an outer cylindrical flange 52, channeled or slotted to provide jaws engaging splines or juive 53 on the periphery of plate 117, so as to prevent relu4 (lll .lilla Ell) tive rotation of the plate `and .fitting l.

AThe fitting also has an inner cylindrical tia-nge or sleeve et which is channeled or ,a bearing` lit about spacer QG ani'lflhe periph# ery ol Harige 27.

At the inward end ot the threadedportion et' the shi 'l'tcr,tlie latter is provided n'itha flange 60. it the outer end ot' thc threaded portion an annular' groove Gl is eut in the shifter to receive a ring G2, which may be a split or snap ring', and which projects sutliciently to overlap the inward portion et plate l? or its threads. Bing GQ and llange GO are so located as to properly estab lish the limits ot longitudinal movement ot pressure plate l? and its connected parts in both directions in relation to the shifter, or to limitoutward movement of tlvA shifter in certain cases, and also flange limits the rotary `movement ot' the pressure member and its associated parts in one direction of movement.` lVhen the pressure member a? in its outer position, as shown in Fig. f2, there is a substantial clearance at between the flange and the `inner face 4.ot the pressure plate, and this clearance indicates the total relative travel of the pressure member and shifter.

The outward end etV spindle G ot reduced diameter and is provided with a screw thread to receive an adjustable spring abutment or nut 7l which may have any suitable locking' device 72. A shoulder T5 is formed on the spindle and yieldable pressure means, specili ially a helical spring; 7G, is pressed between this should 1r and abutment 72. washers 7T and 78 being` provided, preferably, to `pronrly locate the inward end ol' the spring;1 and provide proper cle*L rance for shifter travel.

rlhe appliance is designed 'greater resistance to vehicle spring;l n'iovement in one direction than in the other, and it is usually preferred to oppose the lreatcst resistance to vehicle spring: recoil. lt will.therefore be assumed in the following1 operative description that the appliance Qis properly arranged on the vehicle lo acl in the manner statcih but skilled persons will easily understand that it may readily be adapted to oppose the greatest resistance to vehicle spring` compression byproper rearrangement or relocation; and the functional description will then be equally pertinent when suitable changes are made in words indicating position or direction et' movement.

TWhen the screw threads l5 and le have a right hand lead as shown, the end ot lever ltmoves clockwise (Fig. l). when the veshiter Al() to move outward.

slight normal clearance between the outer to oppor-:e

hicle axle approaches the trame dui-inni vehicle `spring)l compression, and counterctloelrwise during `vehicle springrecoil.` Fig.` Z shows the parts astliey are positioned at the end et a recoil movement. Any considerable recoil is 'followed by an axle reaction or vehicle springl compression. Assuming this to be a small movement, `the rotary structure including the lever, inner housing l0, and the rotor` plates 35, rotate slightly about the spindle and by `trictional contact ol the discs the cooperating discs 50, littine` 5a and the pressure plate 4T turn simultaneously. As soon as screw thread clearance is taken up, the rotation ot plate l? et fective through the lscrew threads, causes the There, is a end ot' the shifter and washer T7. lVhen the vehicle is running over comparatively smooth roads the stated moveme t, due to the slight spring jiggle caused by minor irregularities, is so small that the total clearance, including` thread clearance and the shifter clearance just mentioned will not be fully taken up. i

Spring 7G is normally compressed between the abutment 7l and spindle shoulder `75, erin other words, the spring` is seated and inactive. There is therefore no appreciable lresistance to the stated slight aigle movement, the entire rotary structure turning on -I l N 1 it bearing about die spindle. Vernole spring recoil movements under similar conditions are also so small that the rotor movement within the tree range just described. There is therefore no interference with the normal resiliency ot the vehicle springs while y running over smooth roads.`

When 'the vehicle axle moves any considerable distance away trom the iframe `recoil movement which may bc called lor convenience the wind-up period, duringl which spring i6 is znlditionally compressed. The friction value atfthe `point olf Contact between the rotor and ring 20 or between ring 20 and plate l it the ring turns, is, however, preferably small for reasons above stated and this ettect may in most cases be considered negligible. Resistance is, however., during` this period afforded to the arm movement by theworli required to compress rlbcre is aslight jtrielional reels` ciently indicated in the drawing.

the spring. These conditions continue during the short travel of arm 14 necessary to bring'the shifter flange GO in Contact with plate 47. Further rotation of the plate or pressure member and its connected parts is then prevented by engagement with theirrevoluble shifter and slippage immediately begins between all of the friction disc surfaces, with a pressure on each surface equal to the spring pressure transferred to the shifter and pressure member 47. This friction resistance during the remainder of the spring recoil Vmay be made of a suitable, substantial value, with moderate spring pressure and a reasonable or small average diameter of the friction discs, by providing a considerable number of discs, the approximate number of discs used in actual practice in one form of the device being soilip An important feature of the invention is the design or arrangement of other parts so that this very substantial number of discs can be employed while the size of the appliance is kept within desirable limits.

At the end of recoil movement any small or large vehicle spring compression, which usually immediately follows, will cause arm 14 to move clockwise, (as viewed in Fig, 1) and during this nuwement there is usually very little or practically no resistance and in same cases the arm movement is actually facilitated by the action of spring 7G which when the screw threads are of a suitably steep pitch acts through the nut and screw threads to rotate plate 47 in the same direction that the lever arm 14 is moving. After a veryvsmall angle of arm movement. spring 76 seats on the spindle shoulder and its thrust is again self-contained and ineffective in the operation of the device. If the stated arm movement continues beyond this point, during a small additional angle of such movement,- shifter 40 moves :farther inward without any substantial effect upon other parts. Beginning at the instant when spring 7 6 seated on the spindle shoulder, the friction discs are free from any spring pressure and are free to slip relatively, and the resistance to arm movement to the end ot' any vehicle spring compression stroke therefore only that due lo the slight dragl of the friction discs and their lubricant. There is, howewzr. a very substantial tendency tofree the plates from actual contact with each other, dueto the movement of the jaws 55 along' with plate 47, this movement tending to drag the set of discs which engage these jaws outward, while the other set of rotor plates tend to remain in fixed position by their engagement with the jaws 31.

' It is desirable to prevent the shifter from moving inward more than a moderate amount. because if it is permitted to move far in, its outer end will become widely separated from the inner end of spring 76 or washer 77, and then the outward travelv wouldhave to be correspondingly great during the next vehicle spring recoil before spring 76 became effective to apply resistance to such movement. It is mainly for this purpose that means such as ring 62 employed, to limit the inward movement of the shifter in a manner which is obvious in Fig. 2 and as there shown,` this inward shifter movement is stopped when there is only a very moderate clearance between its outer end and washer 77, and therefore spring 76 will be effective in the next vehicle spring recoil movement after arm 14 moves through a very small substantially free angle, as above sufficiently explained.

The housing constituting the principal portion of the appliance is made water and oil tight and a substantial amount of lubricant `is preferably introduced in the housing` to lubricate the screw threads, the shifter where it slides on the spindle, and the friction discs; and the design is such that a sufficient number of discs may be used in compact space to provide the desired friction resistance even when thoroughly lubricated, and when the spring pressure is reasonably low. It is also desirable in many cases to use a fairly heavy or viscous lubricant, such as heavy oil or grease of a suitable grade, and to introduce a sufficient amount of this lubricant into the casing to act also as a cushioning agency between certain moving parts and especially between the shifter and washer 7 7, for the purpose of preventing the more or less noticeable noises, which are faused in some ci ses by shifter movement n1 the absence of any such cushioning agent.

The combined thrust and radial bearing for the rotor structure is so designed that the relatively movable surfaces have an approximately close lit and these surfaces are moreover so arranged that any substmice passing' between them will have to pursue u substantially long and circuitous course. Any slight amount of lubricant which finally reaches the periphery of ring 20 will be then retained by the compressible gaslct I claim l. An appliance olf the character described, conun'ising a menlber arranged for connection to a lvehicle part such as the frame or axle, a rotor structure arrangerl for relative oscillation and including a lever arm and parts forming a casing, friction means, yieldable pressure means and inclined operating means within the casino, and a thrust bearing to prevent substantial axial movement of the rotor structure.

An appliance of the character described, comprising a member arranged for connection `to a vehicle part such as the frame or axle, a rotor structure arranged lll?) lill) `and a combined radial and thrust bearing including a part secured to said member and a cti-operating` part secured to the rotor structure and serving to guide the rotor structure in its oscillation and substantially prevent axial movement.

3. An appliance of the character` described, comprising a member arranged for connection to a vehicle part such as the frame or axle, a rotor structure arranged for relative oscillation and including" a lever arm` and parts forming a casing, friction means within the casing, said friction means including friction members, yieldiable pressure means, and relatively fixed and movable inclined members controlling` the application of the pressure of said lyieldable means to the friction members, and a thrust bearing preventing substantial axial movement of therotor structure.

i 4l, A shock absorber or similar device comprising a base adapted for coni'iectionto` a vehicle part, a spindle extending therefrom, a shifter movable axially on the spindle, means preventing'shifter rotation and arranged to avoid interference with inward shifter movement, a pressure member having' an inclined member co-operating With the shifter, means for limiting,` inward movement of the shifter in relation to the pressure member, a spring, means normally maintainingI the sprin in inactive conde tion, at least one friction member connected irrevolubly to the pressure member, a rotor structure including parts forming` a casing surrounding and enclosinp` the spindle, shifter, pressure member and spring, and at least one friction member connected irrevolubly to the rotor structure.

it shock absorber or similar device comprisme a base adapted for connection to a vehicle part, aspindle extending therefrom, a shifter movable axially ou the spindle, means preventing' shifter rotation and arranged to avoid interference with inward shifter movement, a pressure member having an inclined member' co-operatingr with the shifter, means for limiting inward morementof the shifter in relation to the pressure member, a spring, means normally maintaining` the spring in inactiix` condition, at least one friction member connected irrevolubly to the pressure member, a rotor structure including parts forming' a casing' surroumling and enclosing the spindle, shifter, pressure member and spring, and at least one friction member connected irrevolubly to the rotor structure, and a thrust bearing' on the base co-operating' with an outer surface of the rotor structure.

6. A shock absorber or similar device comprising a base adapted for connection to a vehiclepart, a spindle extending therefrom, a shifter movable axially on the spindle, means preventingv shifter rotation and arranged to avoid interference with inward shifter movement, a pressure member having' an inclined member cooperating),` With the shifter, means for limiting,` inward movementof the shifter in relation to the pressure member, a spring, means normally maintaining the spring,` in inactive condition,

at least one friction member connectedirrevolubly to the pressure member, a rotor structure including parts forming' a. casing); siirroumlinp,l and enclosing the spindle, shifter, pressure member and spring, at least one friction member connected irrevolubly to the rotor structure, and a combined rotary and thrust bearing for the rotor structure including an element lixed to the rotor structure and an element ixed to the base. i

"7. A shock absorber or similar device com-` prising a base `adapted for connection to a vehicle part, a spindle extending therefrom, a shifter movable axially on the spindle, means prevent-ingl shifter rotation and arranged to avoid interferenceivith inward shifter movement, a pressure member having an inclined member (5o-operating Withthe shifter, means for limiting inward movei nientof the shifter in relation to the pressure member, a spring, means normally maintaining the spring in" inactive condition, at least one friction member connected irrevolubly to the pressure member', a rotor structure including` parts forming` a casing;`

surrounding and enclosing the spindle, shifter, pressure member and spring, at least one friction member connected irrevolubly to the rotor structure, the casing` being suliistantially greased tight, andthe rotary `and thrust bearingl being` arranged to `provide a lona` and approximately tight leakage path and thus to substantially prevent escape of lubricant. i

A shock absorber or sii'nilar device comprisiip` a baite adapted for connection to a vehicle part,a spindle attending: therefrom, a shifter `'movable axially on the spindle, jaws on the base and shifter preventing` shifter rotation `and dimensioned to avoid interfercncewith inward shifter movement, a pressuremember having,l screw thread. engagement with `the shifter, means actingl between the pressure member and shifter to limit its movement with relation to the pressure member inboth directions, a spring', means normally maintaining the springl in inactive condition with one end arranged for shifter contact to exert spring' pressure through the shifter to the pressure member, a plurality of friction discs connected irrevolubly to the pressure member, a rotor structure including parts formingI a casing lll) surrounding and enclosing the spindle, shifter, pressure member and spring, and a plurality offriction dises inter-fitting with those above mentioned and connected irrevolubly to the rotor structure.

9. A shock absorber or similar device comprising a base adapted for connection to a vehicle part, a spindle .extending therefrom, a shifter movable axially on the spindle, jaws Yon the base and shifter preventing shifter rotation and dimensioned to avoid interference with inward shifter movement, means acting between the pressure member and shifter to limit its movement with relation to the pressure member in both directions, a spring, means normally maintaining the .spring in inactive condition with one end. arranged for shifter contact to exert spring pressure through the shifter to the pressure member, a plurality of friction discs connectw ed irrevolubly to the pressure member, a rotor structure including parts forming a cas ing surrounding and enclosing the spindle, shifter,`pressure member and spring, a plurality of friction discs inter-fitting with those above mentioned and connected irrevolubly to the rotor structure, and a thrust bearing member on the base co-operating with an outer surface of the rotor structure.

10. A shock absorber or similar device comprising a base adapted for connection to a vehicle part, a spindle extending therefrom, a shifter movable axially on the spindle, jaws on the base and shifter preventinglr shifter rotation and dimensioned to avoid interference with inward shifter movement, a pressure member having screw thread engagement with the shifter, means acting between the pressure member and shifter to limit its movement with relation to the pressure member in both directions, a. spring, means normally maintaining the spring in inactive condition with one end arranged for shifter' contact to exert spring pressure through the Ashifter' to the pressure member, a plurality of friction discs connected irrev olubly to the pressure member, a rotor structure including parts forming afcasing surrounding and enclosing the spindle, shifter, pressure member and spring, a plu rality of friction discs interiitting with those above mentioned and connected irrevolubly to the rotor structure, and a combined rotary and thrust bearing for the rotor struct-ure including an element fixed to the rotor structure and an element fixed to the base. y

11. A shock absorber or similar device comprising a base adapted for connection to a vehicle part, a. spindle extending therew from, a shifter movable axially on the spindle, jaws on the base and shifter preventing shifter rotation and dimensioned to avoid interference with inward shifter movement, a pressure member having screw thread engagement with the shifter, means acting between the pressure member and shifter to limit its movement with relation to the pressure 'member in both directions, a spring, means normally maintaining the spring in inactive condition with one end arranged for shifter eotaot to exert spring pressure through the shifter to the pressure member, a plurality of friction discs connected irrevolubly to the pressure member, a rotor structure including parts forming a casing surrounding and enc-losing the spindle, shifter, pressure member and spring, a plurality of friction discs, interiitting with those above mentioned and connected irrevolubly to the rotor structure, a combined rotary and thrust bearing for the rotor structure including an element fixed to the rotor structure and an element fixed to the base, the casing being substantially grease tight, and the rotary and thrust bearing being arranged to provide a long and approximately tight leakage path and thus to substantially prevent escape of lubricant.

12 An appliance of the class described comprising a member adapted for connection to a vehicle part such as a frame member, another relatively revoluble member adapted for connection to another vehicle part such as an axle, friction means intermediate the members, a spring, an axially movable actuator, a pressure plate, means by which rotary movement of the pressure plate moves the actuator axially, and means for limiting movement of the actuator in one direction.

13. An appliance of the class described comprising a member adapted for connection to a vehicle part such as a'frame member, another' relatively revoluble member adapted for connection to another vehicle part such as an axle, friction means intermediate the members, a spring, an axially movable actuator, a pressure plate and means by which rotary movement of the pressure plate moves the actuator axially, the spring heilig arranged to apply friction iiressure to said fricw tion mea-ns when the actuator is moved in one direction, and a stop acting between the actuator and the pressure plate to prevent excessive movement of the actuator in the other direction.

Signed at New York ,in the county of New York and State of New York this 5th day of January, A. D. 1925.

RAYMOND P. LANSING. 

